Detergent compositions which directly contact skin such as shampoos, body detergents and the like are required to cause little irritation to the skin in addition to having detergency, foaming performance and good feel upon use. Sulfate-type surfactants, which have been widely used as a detergent component, are high in foaming performance, but sometimes irritate the eyes during shampooing and are liable to roughen hands and skin of the person having sensitive skin over long-term use. Detergent compositions containing as a main component a so-called low irritating surfactant such as an acetate-type surfactant, an amphoteric surfactant, or a surfactant having a sugar skeleton are poor in detergent effect and foaming power, thereby failing to give a satisfactory detergent. Phosphate ester-based surfactants, a kind of anionic surfactant, cause lowered irritation to the skin or the like and are known as a mild surfactant. However, the phosphate ester-based surfactants have a problem that they are poor in water solubility in a certain pH range and in hard water, and are poor in foaming power although their detergency is satisfactory Phosphate esters having ethylene oxide introduced thereto to improve water solubility are known (for example, JP2001-107079 A and JP 2001-181677 A). Although the ethylene oxide-introduced phosphate esters are improved in solubility compared with phosphate esters not having ethylene oxide, their foaming power is insufficient. Therefore, detergent compositions containing the ethylene oxide-introduced phosphate esters or the phosphate esters not having ethylene oxide have a problem that they are low in versatility, specifically they are poor in foaming in a wide range of pH, foaming in hard water and in sebum resistance.